Sync PRs should be auto-mergable if check-enforcer is green

[mikeharder]

Sync PRs should be auto-mergable if check-enforcer is green, even if some of the individual checks are red. For example, this PR was not auto-mergable because python - template failed, even though I ran /check-enforcer override.

https://github.com/Azure/azure-sdk-for-python/pull/14754/checks

Here's the log showing the auto-merge failure:

https://dev.azure.com/azure-sdk/internal/_build/results?buildId=588939&view=logs&j=f6a7114c-32c6-5cc4-d467-98fb1350225d&s=7d381cb2-73e5-5ace-6bc2-80e6cde2a5b2&t=a2695e80-e975-5318-3c29-d781630e749d&l=21

[chidozieononiwu]

This has been fixed by removing inclusion of internal template runs on the sync PR checks.
#1154

[mikeharder]

This still appears to be an issue:

##[warning]https://github.com/Azure/azure-sdk-for-ios/pull/1412 is blocked (unstable).
Please ensure all checks are green and reviewers have approved.

https://dev.azure.com/azure-sdk/internal/_build/results?buildId=2033489&view=logs&j=f6a7114c-32c6-5cc4-d467-98fb1350225d&s=b0f91f5f-86bb-51b4-905a-b77da63d1728&t=92d3002b-c214-53f7-faf6-6294b17e07f4&l=17

Pipeline "ios - client - ci" was failing due to issues in main. I did /check-enforcer override on the sync PR, but the pipeline still blocked because it couldn't merge it. I needed to manually merge the blocked PR.

[weshaggard]

After investigating further there is actually go good way using the rest api or the graphql to fully check if a PR can be merged or not. We are relying on the mergeable_state property in the rest api (https://github.com/Azure/azure-sdk-tools/blob/main/eng/scripts/Verify-And-Merge-PRs.ps1#L47) but it is undocumented and in both cases it returns "unknown" before and after the check-enforcer override is triggered. Given I don't see a great way to handle this and we have an easy workaround, which is to just merge the PR manually, I'm going to close this issue.